Automatic train control



July 5, 1932. F; w JR 1,866,099

AUTOMATiC TRAIN CONTROL Filed Feb. 4, 1929 I W V 2 25 4 4 r0 TRAIN -%l NUT/V5 POWER 3 TO TRACK CIRCUITS SIG/VAL CIRCUIT /4 RACK SIG/ AL CONTROL CIRCUIT j EINVENTOR k l l BY I 444 ATTORNEY Patented July 5, 1932,

4 UNITED sre'rss FRANK w.ensEY,.rR., OF NEW HAVEN, CONNECTICUT, AssIGNO 'ro'irHE sArmY CAR HEATING amenrnve COMPANY, A CORPORATION OF NEW JERSEY AUTOMATIC TRAIN CONTROL 3 Application filed February 4, i929. SeriaLNo. 337,276.

' i This invention relates to train con'trol'systems and more particularly to equipment of this character wherein the movement of a railway locomotive, car, or train,'or other 5 vehicle, is automatically controlled in accordance with, the traflic condition of the track in advance of the train. 7

One of the objects of this invention is to provide a practical and effective railway 10 signaland control system of simple construction and maximum reliabilityofoperation; Another object is to provide an eificientsignal system of the characterdescribed for automatically indicating in a moving vehicle the condition ofthe track in advance thereof and for automatically controlling the movement of the vehicle in response to such condition. Anotherobject' is to provide a cabsignalling and train-control system of the above-mentioned nature in which reliable communication may be established between devices along the track and cooperativede vices upon the'trainor vehicle, inductively, and without the use'of contact collectors or other sliding or rotating devices. Another object thereof is to providefor positive and reliable operation of the signal and control devices irrespective of local disturbances, such as disturbances in the vehicle-carried circuit or circuits, and, more particularly,

irrespective of conditions effecting fluctuations and ch'anges in the train receiving cir cuitdue to fluctuations at or in the source of electrical potential from which the circuit derives normally its energizing current.

Another object is to provide a simple, practical and reliable system of the above nature wherein the vehicle-carried circuit or cir cuits or parts thereof may be safely supplied 40 with energy from sources that, for example,

supply also motive energy to electrical driving equipment, electrical auxiliaries, remote.

control systems, and the like. A- further object is to provide a system of thejabove-mentioned nature, the] regular and safe opera tion of which'will not be detrimentally affected by fluctuations andvariations in the source of energy, therefor or in the output of the source due to the-associationofsuch source with the regular or other electric train equipmenta Another object is to provide asystem in which current changes in a relay system, determined by track; condi-v tions, serve to actuate train-controlling or signalllng devices, whichx'will be protected against actuation of said devices by changes 1 in the energizing current of the relay system brought about by'causes other thanthe condition of the track in advance. Other'objects will be in part obvious or inpart pointed out hereinafter. p 1 p 7 The invention accordingly consists-inthe features of construction, combinations of ele-; ments and arrangementsof parts which will be exemplified in the structure to be heroin after described and the scope of the application of which will be lowing claims. '5'

indicated in the fol- I In theaccompanying drawing, is

shown an: embodiment of my invention, the single figureof the drawing shows diagram matically a preferred form of'my invention. 7 Referring now to the drawing, it is first to be noted that, for the sake of greatersimplicity of illustration, certain parts of the system or apparatus are either'diagrammaticaL ly indicated or are omitted since they may take any suitable or appropriate form and since the details thereof do not formany'part of this invention. For example, there is shown'a relay l0 suitably relatedto theroadbed and track circuit and actuated or controlled by suitable'circuits, relays, or the like, in accordance with-the condition of the trackin advance ofthe moving vehicle, and. the relay. itself may, inan'y suitable manner, coact in effecting or controlling other or related circuits, Since the details of the cir cuitsassociated withrthe relay lQfo'rm no 0 v part of this invention, such circuits are not illustrated. Y i j j a Associated with the roadbed and prefer ablypositioned adjacent or in between the rails is an electromagnetic device generally indicated at 11; this device comprising anironcore 12 and a winding 13 about the core 12, the winding 13 being controlled, as at the switch member 14, by therelay 10/ It will be understood that'any suitable number of suitably spaced devices 11 are associated with the roadbed or track rails, in accordance, for

- example, with the number and length of the 'to coact with the fixed device 11 associated with the roadbed. The device 15 includes an iron core 16 provided with certain energizing windings. These windings may be energized from any suitable source, but, as illustrative.

of certain of the difliculties which my invention overcomes, the windings are supplied with energy from a generator. 17 mounted.

upon the vehicle with which is associated a storage battery 18 connected in circuit 1. The

generator 17 is driven by a motor 19 which 180811 88 its energy from, forexample, the

transmission circuit which supplies the vehis cle .w1th' electric motive power. The generator'17. supplies energy preferably at much less voltage than the voltage of the transmis .sion line to any appropriate auxiliary de -VlCGS, such as train control circuits, lamp cir-v cuits, signalling devices, etc;, and'to lnsure the supply of energy to such devices during periods when the generator 17 is not'operating,-.the generator 17 maintains in substantially charged condition the storage battery 18. Any suitable automatic switch, indicated at 20, may be provided to automatically connect and disconnect thegeneratorand storage battery. In the present embodiment a lamp circuit is indicated at 2 in the drawing, and a train signalling or control circuit is indicated by a legend. 7

.In certain preferred forms of installation, themotor 19 is constructed and designed to start, without starting transformers or re sistances, immediately upon the line voltage beingimpressed thereon, and in any event the motor is started and stopped in accordance with the supply or interruption ofpower in the transmission line. The starting of the motor 19 under such circumstances oftentimes takes place frequently andis so instantaneous that the generator .17 builds up so" rapidly as to cause a substantial surge in potential and current in its output. While such surges may not be harmfulwith respect to certain of the devices supplied with energy by thegenerator,yet it has'been found that suchifiuctuation, surge,,or the like, has been the cause of actuating the train signal and control circuits irrespective of the condition of the track in advance. A dominant aim of this invention is to prevent such improper actuation of the train signal and control cir- Now, referring to the drawing for a more detailed understanding of the present control system, the electromagnetic device 15, which may be calleda receiver, lscarried by soine part of a locomotive or other railway vehicle in a suspend-ed position over the roadbed or track. At predetermined positions along said roadbed, the track members or'inductors 11 are secured in such position as to come within the magnetic field of the receiver as the train passes along the track, in such a manner as a to shortenthe air gap insaid field and decrease the reluctance thereof. I

The normally shorted winding 13 on the inductor member is connected by means of the relay lO'to track circuits,not shown, in

is a primary winding 21 connected to the storage battery by means of circuit 3, and on the other leg of said magnetic core is a secondary winding'22, whichforms part of a circuit 4, connected in parallel with said primary circuit 3, as shown In series with said secondary winding 22 in said circuit/1 is a relay 23, which is normally energized by the current in circuit t to keep said circuit closed.

Before describing other features shown in the drawing, the normal operation of the devices already described will be explained. With the train running freely on open signal, the primary coil 21 of the receiver'receives a substantially constant direct cur: r 100 rent from; the storage battery, 'andflat the same time the relay 23 is energized by its connection to the storage battery to maintain the relay circuit 4 in closed condition. Now, should the train pass over a section of track so as to bring the receiver 15 in juxtaposition to one of said track inductors 11,.and should the conditions obtaining in the trackin advance of the train be such'as to give a clear signal, the track relay shown in the drawing at 10 would maintain closed the circuit through the winding 13 upon said. inductor; If, howeventraflic conditions should be such as to set a stop or other warning signal, the relay" 10 would trip and open-circuit the winding 13, and, as the inductor passes under the poles of the receiver, the air gap in the magnetic field of said receiver being suddenly shortened and the reluctance. of the magnetic circuit reduced thereby, a sudden increase followed by a sudden decrease in the magnetic flux through the-core 16 would take place and induce. voltage in the second ary winding 22, in opposition to the normal current fiowing'through the relay circuit.

Specifically a single cycle of 'A. C.- will be induced in winding 22, one-half of which cycle is in opposition to the normal current'fiowingthrough said relaycircuit. This opposing-current, being ofsufficientstrength to trip the relay 23,would set in operation or control the operation of the signalling or control devices maintained in. the train control circuits. If, however, the winding upon the trackinductor be close-.circuited, the changing flux through said inductor as the latter passes under the vehicle-carried receiver'will build up a current in said closed circuit which will react upon said magnetic inductor to oppose the lines of force received from the magnetic circuit of the receiver 15, and as equilibrium will not be restored until the parts" have been separated by the onward movementof the train, there will not be in duced in the relay circuit 4L- suflicient current to trip the relay 23 and actuate the traincontrol circuit. 1 r y But it is to be noted that fluctuations at the source of direct current, in this case the storage battery 18, if of suflicient scope, will also serve to cause current changes in the pri mary 21 of the receiver 15 and induce in the secondary 22 thereof, currents opposed to the normal current in the relay circuit 4, which induced current may be of suflicient strength to permit the tripping of the relay 23 andproduce activity in the train control circuits. This result is, of course, undesirable and to be avoided.-

In order toovercome the undesired efleots of changes in the battery potential, due to 1 conditions in the load or charging circuits '1 and 2, applicant has associated afilter circuit with the vehicle-carried circuits which 0011-. trol the train control circuits. In the figure, there is shown at 24: a choke coil connected in the battery circuit 3; and a condenser 25 .is connected across the storage battery and across the relay circuit4. With thesedevices connected as shown, any sudden'change of current values in the circuit 3 and re ceiver primary 21, due to changes of potential at the'battery, will be opposed by the impedance of the choke coil 24. As a result, current changes in the secondary 22 of the receiver and in the relay circuit 4 will be of such limited value thatall danger of the accidental tripping of the relay 23 and consequent actuation of the train control devices will beaverted. r

In order to provide a path which will pass without choking, current changes in-the relay orcuit 4, due to the influence of the track inductor 11 upon the secondary winding22' of thereceiver 15, when traflic conditions are. such as to open-circuit the winding 13 on the said track inductor, the condenser 25 is connected, as shown.

and also about the primary winding21 or" thereceiver and will pass current changes' originating in the receiverjsecondary 22 to trip the relay switch.

From the foregoing, it will be seen that This condenser is con-g nected as a'by-pass about the storage battery tical and reliable manner; that few moving parts are employed which might get out of order and reduce the efficiency of the system; I

and that a train control system hasbeen devised which may safely be used, with power taken from a convenient source, even though that source be subject to sudden and wide potential of its electrical variations in the output.

As many possible embodiments may be made of the above-invention and as many the accompanying drawing is to be inter-- pretedvas illustrative and not in alimiting sense. I'claim: I I M 1. In an automatic train control system,

in combination, a source oit' potentialsubject to fluctuations, two train-carried inductively coupled circults eachhavmg associated therewith electro-responsive means energized by K said source and responsive to track cond tions, I i a relay connected with both of said circuits,

and inductance means and capacitymeans forming a filter for preventing fluctuations 1n sald source from actuating said relay.

2. In a; train control system,-incombinai ave ic e-ca-rie s r o 0 en his ton, h l 1 d on ce t t tla ub 1605 to I sudden variations under certain operating conditions, a train-controlling "device on the vehicle," a relayforactuating said train-controllingdevice, a pair of inductively coupled circuits connectedrtosaid source, one

of said cir'cui'tS including jsaid relay,'track meansadapted inductively to act upon'said inductively coupled circuits to trip said relay under predetermined traflic conditions, and a filter means associated with said. circuits adapted to prevent changes at the said source of potential from tripping said relay and permitting the normal operation of said relay by said track device. V

3: Ina" train control system, in combination, a vehicle-carriedsource of potential sub 'ectitosudden variations under certain operating conditions, axtrain-controlling device,'on' theve'hicle, a relay for actuating said train-controlhng dev1ce,a pair. of 1I1ClL1Ct1V6ly coupled circuits vconnected to said source,'one

of said circuits including said relay,"track meansin-said other circuit adapted to oppose the passage of current variations due to' voltage changes at sa d source. 7

- a. In atrain control system, in combinaa011, aivehicle-carried source'ot potential subject to'sudden variations under certain operating cond1t1ons, a tram-controlling de-.

vice on the vehicle, a relay for actuating said train-controlling device, a pair of inductively. coupled circuits connected to said source, one of said circuits including said relay, track means adapted inductively to act upon said 'inductivelycoupled circuits to trip said relay under predetermined traflic conditions, a condenser in said relay-containing circuit adapt- -ed to pass current variations therein due to the influence of said track means, and a choke coil in said other circuit adapted to oppose the passage of current variations due to voltage changes at the source.

, 5. Ina train control system, in combination, a source of potential carried on a vehicle, a train-controlllng devlcein the vehlcle,

V a vehicle-carried electromagnetic device suspended overthe track and comprisinga primary anda secondary winding, a relay, a'circuit including said source, said secondary winding and said relay and controlling sa1d vehicle-controllingdevice, a circuit including said source and said primary winding, a track inductor positioned inthe path oftravelof the magnetic field of said electromagnetic device and adapted to induce current in said relay-containing circuit to trip said relay,-

and filter meansassociate'd with said circuits adapted to prevent changes at the source from tripping said relayand permitting the normal operation-of said relay by said track inductor.

6. In a train; control system, in combination, a vehicle-carried storage battery connected to be intermittently charged'by a generator, a train-controlling devicein the vehij circuit including said battery, said secondary.

cle, a vehicle-carried electromagnetic device suspended over the track and comprising a primaryanda secondary winding, a relay, a circuit including said battery, said secondary winding and said relay and controlling said vehicle-cont olling device, a circuit including said battery and said primary winding, a track inductor positioned in the path of travel of the magnetic field of said electromagnetic device and adaptedto induce current in said relay-containing circuit to trip said relay,

means in said relay-containing circuit adapt- .ed to pass current variations'therein due to the influence of saidtrackmeans, and means in said other circuit adapted to oppose the passage of current variations due to voltage changes at said battery.v V y Y I 7. In a train control system, in combination, a vehicle-carried storage battery 'con. nected to be intermittently charged byia generator, a train-controlling device in the vehicle, a'vehicle-carried electromagnetic device suspended over the trackand comprising a primary and'a secondary winding, a relay, a

- winding and said relay and controlling said vehicle-controlling device, a circuitincluding said battery and said primary winding, a

t I'ElCk fIIlCl1lCtO1J positioned at thepath of travel of them agnetic field of said electro magneticdevice and adapted to induce current in said relay-containing circuit to trip said relay, a condenser in said relay-contain ing circuit adapted to pass current variations therein due to the influence of said track means, and a choke in said other circuit adapted to oppose the passage of current variations due to voltage changes at said battery.-- i o 8. In a train control system, in combination, a vehiclescarried storage battery con- 7 nected to be intermittently charged by agenerator, a vehicle-carried electromagnetic device suspended over the track andcomprising aprimary and a secondary wlnding, a

train control relay, a circuit including said battery and said primary winding, a circuit connected in parallel with said primary winding and including said secondary winding and said relay, a track inductor positioned in the path of travel of the magnetic field of said electromagnetic device and adapted to induce current in said relay-con taining circuit to trip said relay, a filter condenser connected to by-pass both of said circuits, and a choke connected in said first'circuit in series with said battery and said primary Windin o 9. In an automatic train control system, in combination, a source of potential subjectto fluctuations, two train-carried inductively coupled circuits each having associated therewith electro-responsive means energized by said source and responsive to track conditions, a relay connected with both of said circuits, and means 1 forming an electric filter associated with one-of said circuits for filtering'out fluctuations in said source'and preventing said fluctuations fromfactuating said relay. r V V V 10. In an automatic train control system,

in combination,'a vehicle, carrying a circuit having included therein a relay and electroresponsive means and. a storage battery for locally energizing said relay and said electro-responsive means; means associated with the trackcalong Whichsaid vehicle runsadapted to aflect said electro-responsive means in accordance with the conditions of the track; a source of potentlal .for charging said storage V battery; an automatic switch for con necting said source to the battery when the characteristics of the formerare appropriate for charging the battery; and electric filter means for preventing fluctuations in the local energizing circuit from actuating said relay.

11. In an automatic train control system, in combination, a vehicle carrying a storage battery having connected thereto two circuits, one of said circuits including a relay and a winding, the other of said circuits including a; winding; a common core for said Windinggjsaid core-being positioned to be aiiected means positioned along the, track;

a source of potential forcharging said stor age battery; and filtering means in said other circuit for preventing fluctuations in the energizing source from reaching the winding in said other circuit.

, means by variations in the reluctance of said 12. In an automatic train'control system,

in combination, a source of electrical energy subject to fluctuations, a magnetic core, a plurality of windings positioned about said core and connected to said source, a relay connected to said windings, and means comprising a filter interposed between said windings and said source whereby fluctuations of said source tending to operate said relay will be prevented.

13. In anautomatic: train control system including a vehicle and a track, in combina-' tion, a source of potential subject to fiuctua-' tions, a magnetic circuit mounted on said vehicle whose reluctance is made to change in accordance with themovement of said vehicle relativeto a cooperating control on said track, means connected to said source operated by the variation in the reluctance of said magnetic circuit, and means comprising an electrical filter connected across said source for preventing variations in said source for ac tuating said first mentioned means, but per- I mitting free actuation of said first mentioned magnetic circuit.

In testimony whereof, I have signed" name to this specification this 18th'day of January, 1929.- I

FRANK W. GODSEY, JRL 

